In the mid-Eighties, Def Leppard and genius producer Robert "Mutt" Lange sold an Everest-sized pile of records by making pop-metal at its most streamlined, glossy and, at times oddly beautiful (their dream-cheese masterpiece "Hysteria"). The band's commercial fortunes took a terminal hit when their partnership with Lange ended, but they've continued to doggedly release new records and search for ways to keep their legacy of crossover greatness alive — 2008's Songs From the Sparkle Lounge featured a collaboration with country star Tim McGraw. Their self-produced new one opens with "Let's Go," a proud, if somewhat beleaguered-feeling, callback to "Pour Some Sugar On Me," where singer Joe Elliott asks, "Do you really wanna do this now?" The next track, "Dangerous," answers that question with a hearty "sure, maybe," by cut-and-pasting the synthetic power-surge of old into a surefooted glam-blam rocker.

Elsewhere, though, the Leps seem uninterested on falling back on old glories, pushing their songwriting in frustratingly inventive and varied directions on the gender-bending disco jammy "Man Enough," the dance-pop-flavored "Energized," the Led Zep-tinged psychedelic folk-blues "Battle of My Own" and the Nashville-minded acoustic ballad "Last Dance." If you're looking for a better reminder of a happier, simpler age, you may have to check out guitarist Phil Collen's new memoir, Adrenalized: "I was waiting for an elevator in a hotel," he writes, recalling the band's American breakout. "A really hot girl whom I had never seen in my life came up to me, pulled my pants down, and went down on me and didn't say a word." Perhaps that type of lightning is only meant to strike once.